BACKGROUND
1. Field
[0001] One or more embodiments relate to a display apparatus and a method of manufacturing
the same.
2. Description of the Related Art
[0002] Mobile electronic apparatuses are widely used. Mobile electronic apparatus have been
widely used recently, not only miniaturized electronic apparatuses such as mobile
phones, but also tablet personal computers ("PC").
[0003] To support various functions, mobile electronic apparatuses often include a display
apparatus to provide a user with visual information such as an image. Because parts
driving display apparatuses have been miniaturized, the proportion of the display
apparatus in an electronic apparatus gradually increases. In addition, as display
apparatuses become thinner and lighter, their range of use has been gradually extended.
In addition, research and development have been carried out on reducing the area of
a non-display area and increasing the area of a display area of display apparatuses.
SUMMARY
[0004] One or more embodiments include a display apparatus which may display an image even
in lateral surfaces and/or corners and a method of manufacturing the display apparatus
to reduce the area of a non-display area and increase the area of a display area.
One or more embodiments include a display apparatus which may reduce defects that
may occur while a display panel is attached to a window cover, and a method of manufacturing
the display apparatus. However, such a technical problem is an example, and the disclosure
is not limited thereto.
[0005] Additional aspects will be set forth in part in the description which follows and,
in part, will be apparent from the description, or may be learned by practice of the
presented embodiments of the disclosure.
[0006] According to one or more embodiments, a display apparatus includes: a display panel
including a display area, a peripheral area, a bending area, and a pad area, where
the display area is configured to display an image, the peripheral area is outside
the display area and does not display an image, the bending area is on one side of
the peripheral area, and the pad area is spaced apart from the peripheral area with
the bending area therebetween; and a lower protection layer arranged on a rear surface
of the display panel and including a first portion and a second portion, where the
first portion corresponds to the display area and the peripheral area, and the second
portion corresponds to the pad area. Here, the first portion of the lower protection
layer includes a material different from that of the second portion.
[0007] A modulus of the first portion of the lower protection layer may be less than a modulus
of the second portion.
[0008] The first portion of the lower protection layer may include poly dimethylsiloxane.
[0009] The first portion of the lower protection layer may include thermoplastic polyurethane.
[0010] A modulus of the first portion of the lower protection layer may exceed about 0 megapascals
(MPa) and less than about 100 MPa.
[0011] The second portion of the lower protection layer may include polyethylene terephthalate.
[0012] The display apparatus may further include a display circuit board attached in the
pad area of the display panel.
[0013] The display panel may be bent in the bending area such that the display area overlaps
the pad area in a thickness direction of the display panel.
[0014] The display apparatus may further include a cover window arranged on a front surface
of the display panel.
[0015] The display area of the display panel may include a flat front display area; a first
side display area adjacent to a first edge of the front display area, where at least
a portion of the first side display area is bent; and a second side display area adjacent
to a second edge of the front display area crossing the first edge, where at least
a portion of the second side display area is bent. The peripheral area of the display
panel may include a corner area arranged at a corner side where the first edge meets
the second edge of the front display area, and the corner area may be adjacent to
the first side display area and the second side display area.
[0016] The display area of the display panel may further include: a flat front display area;
a first side display area adjacent to a first edge of the front display area, where
at least a portion of the first side display area is bent; a second side display area
adjacent to a second edge of the front display area crossing the first edge of the
front display area, where at least a portion of the second side display area is bent;
and a corner display area arranged at a corner side where the first edge meets the
second edge of the front display area. The corner display area may be adjacent to
the first side display area and the second side display area.
[0017] According to one or more embodiments, a method of manufacturing a display apparatus
includes: preparing a display panel including a display area, a peripheral area, a
bending area, and a pad area, where the peripheral area is outside the display area,
the bending area is on one side of the peripheral area, and the pad area is apart
from the peripheral area with the bending area therebetween; attaching a lower protection
layer to a rear surface of the display panel, where the lower protection layer includes
a first portion and a second portion, the first portion corresponds to the display
area and the peripheral area, and the second portion corresponds to the pad area;
attaching a guide film to a rear surface of the lower protection layer; applying tensile
force to the guide film and transforming a shape of the display panel; attaching a
cover window to a front surface of the display panel; and removing the guide film.
A modulus of the first portion of the lower protection layer is less than a modulus
of the second portion.
[0018] The first portion of the lower protection layer may include poly dimethylsiloxane
or thermoplastic polyurethane.
[0019] A modulus of the first portion of the lower protection layer may be greater than
about 0 MPa and less than about 100 MPa.
[0020] The second portion of the lower protection layer may include polyethylene terephthalate.
[0021] The guide film may have a modulus greater than a modulus of the first portion of
the lower protection layer.
[0022] The guide film may include polyethylene terephthalate.
[0023] The guide film may include a central region, a first edge area connected to a first
edge of the central region, and a second edge area of the central region connected
to a second edge crossing the first edge of the central region.
[0024] The display area of the display panel may include a front display area; a first side
display area connected to a first edge of the front display area; and a second side
display area connected to a second edge of the front display area crossing the first
edge of the front display area, and the peripheral area of the display panel may include
a corner area arranged at a corner side where the first edge of the front display
area meets the second edge of the front display area, and the corner area is adjacent
to the first side display area and the second side display area.
[0025] With the guide film attached to the rear surface of the lower protection layer, the
central region of the guide film may include a concave corner not to overlap the corner
area of the display panel in a plan view.
[0026] The display area of the display panel may include a front display area, a first side
display area connected to a first edge of the front display area, a second side display
area connected to a second edge of the front display area crossing the first edge
of the front display area, and a corner display area adjacent to the first side display
area and the second side display area.
[0027] With the guide film attached to the rear surface of the lower protection layer, the
central region of the guide film may include a concave corner not to overlap the corner
display area of the display panel in a plan view.
[0028] The method may further include, after the attaching of the lower protection layer
to the rear surface of the display panel, attaching a display circuit board in the
pad area of the front surface of the display panel.
[0029] At least some of the above and other features of the invention are set out in the
claims.
[0030] These and/or other aspects will become apparent and more readily appreciated from
the following description of the embodiments, the accompanying drawings, and claims.
[0031] These general and specific aspects may be implemented by using a system, a method,
a computer program, or a combination of a certain system, method, and computer program.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The above and other aspects, features, and advantages of certain embodiments of the
disclosure will be more apparent from the following description taken in conjunction
with the accompanying drawings, in which:
FIG. 1 is a perspective view of a display apparatus according to an embodiment;
FIG. 2 is a perspective view of a display apparatus according to another embodiment;
FIG. 3 is an exploded perspective view of a display panel and a cover window of a
display apparatus according to an embodiment;
FIGS. 4A and 4B are cross-sectional views of a portion of a display apparatus according
to an embodiment;
FIG. 5 is a plan view of a portion of a display panel of a display apparatus according
to an embodiment;
FIGS. 6A and 6B are enlarged plan views of a portion of a display panel according
to an embodiment;
FIG. 7 is a cross-sectional view of a portion of a display panel of a display apparatus
according to an embodiment;
FIG. 8 is an equivalent circuit diagram of a pixel circuit of a display apparatus
according to an embodiment;
FIGS. 9A to 9F are side views showing a method of manufacturing a display apparatus
according to an embodiment;
FIG. 10 is a plan view of a guide film and a lower protection layer according to an
embodiment; and
FIGS. 11A to 11J are side views or perspective views showing a method of manufacturing
a display apparatus according to an embodiment.
DETAILED DESCRIPTION
[0033] Reference will now be made in detail to embodiments, examples of which are illustrated
in the accompanying drawings, wherein like reference numerals refer to like elements
throughout. In this regard, the present embodiments may have different forms and should
not be construed as being limited to the descriptions set forth herein. Accordingly,
the embodiments are merely described below, by referring to the figures, to explain
aspects of the present description. As used herein, the term "and/or" includes any
and all combinations of one or more of the associated listed items. Throughout the
disclosure, the expression "at least one of a, b or c" indicates only a, only b, only
c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.
[0034] As the present disclosure allows for various changes and numerous embodiments, certain
embodiments will be illustrated in the drawings and described in the written description.
Effects and features of the disclosure, and methods for achieving them will be clarified
with reference to embodiments described below in detail with reference to the drawings.
However, the disclosure according to the invention is not limited to the following
embodiments and may be embodied in various forms.
[0035] Hereinafter, embodiments will be described with reference to the accompanying drawings,
wherein like reference numerals refer to like elements throughout and a repeated description
thereof is omitted.
[0036] While such terms as "first" and "second" may be used to describe various components,
such components must not be limited to the above terms. The above terms are used to
distinguish one component from another.
[0037] The singular forms "a," "an," and "the" as used herein are intended to include the
plural forms as well unless the context clearly indicates otherwise.
[0038] It will be understood that the terms "comprise," "comprising," "include" and/or "including"
as used herein specify the presence of stated features or components but do not preclude
the addition of one or more other features or components.
[0039] It will be further understood that, when a layer, region, or component is referred
to as being "on" another layer, region, or component, it can be directly or indirectly
on the other layer, region, or component. That is, for example, intervening layers,
regions, or components may be present.
[0040] Sizes of elements in the drawings may be exaggerated or reduced for convenience of
explanation. For example, since sizes and thicknesses of elements in the drawings
are arbitrarily illustrated for convenience of explanation, the disclosure is not
limited thereto.
[0041] When an embodiment may be implemented differently, a certain process order may be
performed differently from the described order. For example, two consecutively described
processes may be performed substantially at the same time or performed in an order
opposite to the described order.
[0042] In the present specification, "A and/or B" means A or B, or A and B. In the present
specification, "at least one of A and B" means A or B, or A and B.
[0043] It will be understood that when a layer, region, or component is referred to as being
"connected" to another layer, region, or component, it may be "directly connected"
to the other layer, region, or component or may be "indirectly connected" to the other
layer, region, or component with other layer, region, or component interposed therebetween.
For example, it will be understood that when a layer, region, or component is referred
to as being "electrically connected" to another layer, region, or component, it may
be "directly electrically connected" to the other layer, region, or component or may
be "indirectly electrically connected" to other layer, region, or component with other
layer, region, or component interposed therebetween.
[0044] In the following examples, the x-axis, the y-axis and the z-axis are not limited
to three axes of the rectangular coordinate system, and may be interpreted in a broader
sense. For example, the x-axis, the y-axis, and the z-axis may be perpendicular to
one another, or may represent different directions that are not perpendicular to one
another (e.g. the directions may cross each other, but need not be perpendicular).
[0045] FIG. 1 is a perspective view of a display apparatus 1 according to an embodiment.
[0046] Referring to FIG. 1, the display apparatus 1 may be used as a display screen of various
products including televisions, notebook computers, monitors, advertisement boards,
Internet of things ("IoT") as well as portable electronic apparatuses including mobile
phones, smart phones, tablet personal computers (PC), mobile communication terminals,
electronic organizers, electronic books, portable multimedia players ("PMP"), navigations,
and ultra mobile personal computers ("UMPC").
[0047] In an embodiment, the display apparatus 1 may have a quadrangular shape in a plan
view. As an embodiment, the display apparatus1 may have various shapes such as polygons
including triangles and quadrangles, circular shapes, and elliptical shapes. In an
embodiment, in the case where the display apparatus 1 has a polygonal shape in a plan
view, the corners of the polygon may be round. Hereinafter, for convenience of description,
the case where the display apparatus 1 has a quadrangular shape including round corners
in a plan view is mainly described.
[0048] The display apparatus 1 may have short sides in a first direction (e.g., an x-direction
or a (-) x-direction) and long sides in a second direction (e.g. a y-direction or
a (-) y-direction). In another embodiment, in the display apparatus 1, the length
of the side in the first direction (e.g., the x-direction or the (-) x-direction)
may be the same as the length of the side in the second direction (e.g. the y-direction
or the (-) y-direction). In another embodiment, the display apparatus 1 may have long
sides in the first direction (e.g., the x-direction or the (-) x-direction) and short
sides in the second direction (e.g. the y-direction or the (-) y-direction).
[0049] Each corner where the short side in the first direction (e.g., the x-direction or
the (-) x-direction) meets the long side in the second direction (e.g. the y-direction
or the (-) y-direction) may be round to have a preset curvature.
[0050] The display apparatus 1 may include the display area DA and the non-display area
NDA outside the display area DA. A plurality of pixels PX may be arranged in the display
area DA. An image may be provided through an array of the plurality of pixels PX.
The pixel PX may be defined as a region in which light is emitted from light-emitting
elements of the display apparatus 1. As an example, the plurality of pixels PX may
each include a red sub-pixel, a green sub-pixel, and a blue sub-pixel. Alternatively,
the plurality of pixels PX may each include a red sub-pixel, a green sub-pixel, a
blue sub-pixel, and a white sub-pixel.
[0051] In an embodiment, the display area DA may include a front display area FDA, a side
display area SDA, and an intermediate display area MDA. The plurality of pixels PX
may be arranged in each of the front display area FDA, the side display area SDA,
and the intermediate display area MDA.
[0052] The front display area FDA may include a flat surface. In an embodiment, a ratio
of the front display area FDA to the display area DA of the display apparatus 1 may
be largest, and thus, the front display area FDA may provide most of an image.
[0053] At least a portion of the side display area SDA may be bent to include a curved surface
and may extend to the outside from each edge of the front display area FDA. In an
embodiment, the side display area SDA may include a first side display area SDA1,
a second side display area SDA2, a third side display area SDA3, and a fourth side
display area SDA4. In an embodiment, at least one of the first side display area SDA1,
the second side display area SDA2, the third side display area SDA3, and the fourth
side display area SDA4 may be omitted.
[0054] In an embodiment, the first side display area SDA1 may be adjacent to a first edge
FDA-E1 of the front display area FDA and may extend to the outside in the (-) y-direction
from the first edge FDA-E1. The second side display area SDA2 may be adjacent to a
second edge FDA-E2 of the front display area FDA and may extend to the outside in
the x-direction from the second edge FDA-E2. The third side display area SDA3 may
be adjacent to a third edge FDA-E3 of the front display area FDA and may extend to
the outside in the y-direction from the third edge FDA-E3. The fourth side display
area SDA4 may be adjacent to a fourth edge FDA-E4 of the front display area FDA and
may extend to the outside in the (-) x-direction from the fourth edge FDA-E4. In this
case, the first side display area SDA1 may be arranged opposite the third side display
area SDA3 with the front display area FDA therebetween, and the second side display
area SDA2 may be arranged opposite the fourth side display area SDA4 with the front
display area FDA therebetween.
[0055] As shown in FIG. 1, the first to fourth side display areas SDA1, SDA2, SDA3, and
SDA4 may each include a bent curved surface with a constant curvature. As an example,
the first side display area SDA1 and the third side display area SDA3 may each include
a bent curved surface around a bending axis extending in the x-direction, and the
second side display area SDA2 and the fourth side display area SDA4 may each include
a bent curved surface around a bending axis extending in the y-direction. The curvatures
of the first to fourth side display areas SDA1, SDA2, SDA3, and SDA4 may be the same
or different from one another. As an example, the curvature of the first side display
area SDA1 may be the same as the curvature of the third side display area SDA3, and
the curvature of the second side display area SDA2 may be the same as the curvature
of the fourth side display area SDA4. As an example, the curvature of the first side
display area SDA1 may be different from the curvature of the second side display area
SDA2. As another example, the curvature of the first side display area SDA1 may be
the same as the curvature of the second side display area SDA2.
[0056] The intermediate display area MDA may be arranged between the front display area
FDA and a corner area CA described below. In addition, the intermediate display area
MDA may be arranged between the side display area SDA and the corner area CA. The
intermediate display area MDA may extend between the front display area FDA and the
corner area CA and between the side display area SDA and the corner area CA. As shown
in FIG. 1, in the case where the display apparatus 1 has a quadrangular shape in a
plan view, four intermediate display areas MDA may be provided.
[0057] In an embodiment, not only the plurality of pixels PX are arranged in the intermediate
areas MDA but also a driver, etc. may be arranged in the intermediate display areas
MDA, the driver being configured to transfer electric signals or power to the display
area DA. In an embodiment, the pixels PX arranged in the intermediate areas MDA may
be arranged over the driver to overlap the driver arranged in the intermediate display
areas MDA in a plan view. In an embodiment, a pixel circuit that drives the pixels
PX in the intermediate areas MDA may be arranged in the front display area FDA, the
side display area SDA, and/or the corner area CA adjacent to the intermediate display
areas MDA.
[0058] The display apparatus 1 of FIG. 1 may be configured to display an image on the side
display areas SDA and the intermediate display areas MDA as well as the front display
area FDA. Accordingly, a ratio of the display area DA to the display apparatus 1 may
increase. That is, in the display apparatus 1 having the same size, the area of the
non-display area NDA may be reduced, and the area of the display area DA may increase.
[0059] The pixels PX are not arranged in the non-display area NDA of the display apparatus
1, and thus, the non-display area NDA may be a region on which an image is not displayed.
The non-display area NDA may include the peripheral area PA outside the display area
DA. The peripheral area PA may surround the display area DA entirely or partially.
The driver, etc. may be arranged in the peripheral area PA, the driver being configured
to transfer electric signals or power to the display area DA.
[0060] In an embodiment, the non-display area NDA may include the corner area CA. The corner
area CA may be arranged on a corner side where two edges of the front display area
FDA that are adjacent to each other meet. As an example, the corner area CA may be
arranged on the corner side where the first edge FDA-E1 meets the second edge FDA-E2
of the front display area FDA. The corner area CA may be adjacent to the first side
display area SDA1 and the second side display area SDA2. As shown in FIG. 1, in the
case where the display apparatus 1 has a quadrangular shape in a plan view, four corner
areas CA may be provided.
[0061] Because the corner area CA is arranged between the side display areas SDA adjacent
to each other and having curved surfaces that are bent in different directions, the
corner area CA may include a curved surface in which curved surfaces bent in various
directions are continuously connected. In addition, in the case where the curvatures
of the side display areas SDA adjacent to each other are different from each other,
the curvature of the corner area CA may gradually change along the edge of the display
apparatus 1. As an example, in the case where the curvature of the first side display
area SDA1 is different from the curvature of the second side display area SDA2, the
corner area CA between the first side display area SDA1 and the second side display
area SDA2 may have a curvature that gradually changes depending on the position thereof.
The curvature discussed in this section relates to curvature from the front of the
device 1 to the rear of the device. That is, the curvature discussed above relates
to curvature along axes parallel to the front display area FDA, rather than curvature
of the corner around an axis perpendicular to the front display area FDA.
[0062] Though the first side display area SDA1, the second side display area SDA2, and the
corner area CA therebetween are described as an example, the description is similarly
applicable to other three corner areas CA.
[0063] FIG. 2 is a perspective view of the display apparatus 1 according to another embodiment.
The same descriptions as those described with reference to FIG. 1 are omitted and
differences are mainly described below.
[0064] Referring to FIG. 2, the display area DA may include the front display area FDA,
the side display area SDA, the intermediate display area MDA, and a corner display
area CDA. The plurality of pixels PX may be arranged in each of the front display
area FDA, the side display area SDA, the intermediate display area MDA, and the corner
display area CDA. Descriptions of the front display area FDA and the side display
area SDA are the same as those described with reference to FIG. 1, and thus, the descriptions
thereof are omitted.
[0065] The intermediate display area MDA may be arranged between the front display area
FDA and the corner display area CDA described below. In addition, the intermediate
display area MDA may be arranged between the side display area SDA and the corner
display area CDA. The intermediate display area MDA may extend between the front display
area FDA and the corner display area CDA and between the side display area SDA and
the corner display area CDA. As shown in FIG. 2, in the case where the display apparatus
1 has a quadrangular shape in a plan view, four intermediate display areas MDA may
be provided. In an embodiment, a pixel circuit that drives the pixels PX in the intermediate
areas MDA may be arranged in the front display area FDA, the side display area SDA,
and/or the corner display area CDA adjacent to the intermediate display areas MDA.
[0066] The corner display area CDA may be arranged on the corner side of the display apparatus
1 and may include a curved surface. Here, the corner of the display apparatus 1 may
be a portion where the short side of the display apparatus 1 in the first direction
(e.g., the x-direction or (-)x-direction) meets the long side of the display apparatus
1 in the second direction (e.g., the y-direction or (-)y-direction). As shown in FIG.
2, in the case where the display apparatus 1 has a quadrangular shape in a plan view,
four corner display areas CDA may be provided.
[0067] The corner display area CDA may be arranged on the corner side where two edges of
the front display area FDA meet each other. That is, the corner display area CDA may
be adjacent to the two side display areas SDA. As an example, the corner display areas
CDA may be arranged on the corner side where the first edge FDA-E1 meets the second
edge FDA-E2 of the front display area FDA and be adjacent to the first side display
area SDA1 and the second side display area SDA2.
[0068] Because the corner display area CDA is arranged between the side display areas SDA
adjacent to each other and having curved surfaces that are bent in different directions,
the corner display area CDA may include a curved surface in which curved surfaces
bent in various directions are continuously connected. In addition, in the case where
the curvatures of the side display areas SDA adjacent to each other are different
from each other, the curvature of the corner display area CDA may gradually change
along the edge of the display apparatus 1. As an example, in the case where the curvature
of the first side display area SDA1 is different from the curvature of the second
side display area SDA2, the corner display area CDA between the first side display
area SDA1 and the second side display area SDA2 may have a curvature that gradually
changes depending on the position thereof. The curvature discussed in this section
relates to curvature from the front of the device 1 to the rear of the device. That
is, the curvature discussed above relates to curvature along axes parallel to the
front display area FDA, rather than curvature of the corner around an axis perpendicular
to the front display area FDA.
[0069] Though the first side display area SDA1, the second side display area SDA2, and the
corner display area CDA therebetween are described as an example, the description
is similarly applicable to other three corner display areas CDA.
[0070] The display apparatus 1 of FIG. 2 may be configured to display an image in not only
the front display area FDA, the side display area SDA, and the intermediate display
area MDA, but also the corner display area CDA. Accordingly, a ratio of the display
area DA to the display apparatus 1 may increase even more. That is, in the display
apparatus 1 having the same size, the area of the non-display area NDA may be reduced,
and the area of the display area DA may increase. In addition, because the display
apparatus 1 includes the corner display area CDA that includes a round curved surface
at the corner thereof and displays an image, the aesthetic sense of the display apparatus
1 may be effectively improved.
[0071] The non-display area NDA of the display apparatus 1 of FIG. 2 may include the peripheral
area PA outside the display area DA. In an embodiment, the peripheral area PA may
entirely surround the front display area FDA, four side display areas SDA, and four
corner display areas CDA.
[0072] Though the display apparatus 1 of FIG. 2 is described as an example, for convenience
of description, the descriptions below are equally applicable to the display apparatus
1 of FIG. 1.
[0073] FIG. 3 is an exploded perspective view of the display panel 10 and a cover window
CW of the display apparatus 1 according to an embodiment.
[0074] Referring to FIG. 3, the display apparatus 1 may include the display panel 10 and
the cover window CW. The cover window CW may be arranged on the front surface of the
display panel 10. Here, the 'front surface' of the display panel 10 may be defined
as a surface facing a direction in which the display panel 10 displays an image.
[0075] In an embodiment, the cover window CW may be arranged to cover the front surface
of the display panel 10. The cover window CW may protect the front surface of the
display panel 10. In addition, the cover window may form the appearance of the display
apparatus 1 and include the plane and the curved surfaces corresponding to the shape
of the display apparatus 1.
[0076] The cover window CW may be attached to the display panel 10 through an adhesive layer
(not shown). The adhesive layer may include an adhesive member such as an optically
clear adhesive ("OCA") or a pressure sensitive adhesive ("PSA").
[0077] The cover window CW may have a high transmittance to transmit light emitted from
the display panel 10 and have a thin thickness to reduce the weight of the display
apparatus 1. In addition, the cover window CW may have strong strength and hardness
to protect the display panel 10 from external impacts. As an example, the cover window
CW may be a flexible window. The cover window CW may protect the display panel 10
while being easily bent according to external force without generating a crack, etc.
As another example, the cover window CW may include glass or plastic. As an example,
the cover window CW may be ultra thin glass ("UTG") whose strength has been reinforced
through chemical reinforcement or thermal reinforcement, etc.
[0078] An image displayed on the display panel 10 may be provided to a user through the
cover window CW that is transparent. That is, it may be understood that an image provided
by the display apparatus 1 is implemented by the display panel 10, and thus, it may
be understood that the display area DA (see FIG. 2) and the non-display area NDA (see
FIG. 2) of the display apparatus 1 are provided to the display panel 10.
[0079] FIGS. 4A and 4B are cross-sectional views of a portion of the display apparatus 1
according to an embodiment. FIG. 4A shows the cross-sections of the front display
area FDA, the second side display area SDA2, and the third side display area SDA3
of the display apparatus 1, and FIG. 4B shows the cross-sections of the front display
area FDA and the two corner display areas CDA of the display apparatus 1. In FIGS.
4A and 4B, the same reference numerals are used for the same elements, and thus, repeated
descriptions are omitted.
[0080] First, referring to FIG. 4A, the display apparatus 1 may include a functional layer
FL and the cover window CW arranged on the front surface of the display panel 10.
In addition, in the display apparatus 1, a lower protection layer 20 may be arranged
on the rear surface of the display panel 10.
[0081] The functional layer FL may be attached to the front surface of the display panel
10 in the form of a film through an adhesive member. For the adhesive member, a general
adhesive member known in the art may be employed without limitation. As an example,
the adhesive member may be an optical clear adhesive (OCA) or a pressure sensitive
adhesive (PSA).
[0082] In an embodiment, the functional layer FL may be an optical functional layer configured
to reduce the reflectivity of light (external light) incident toward the display panel
10 from the outside and/or improve the color purity of light emitted from the display
panel 10. In this case, the functional layer FL may be a polarizing film including
a retarder and/or a polarizer. The retarder may include a λ/2 retarder and/or a λ/4
retarder.
[0083] The lower protection layer 20 may be attached to the rear surface of the display
panel 10 in the form of a film through an adhesive member. For the adhesive member,
a general adhesive member known in the art may be employed without limitation. As
an example, the adhesive member may be an optical clear adhesive (OCA) or a pressure
sensitive adhesive (PSA). As an example, the lower protection layer 20 may have a
thickness ranging from about 50 micrometers (µm) to about 400 µm.
[0084] In an embodiment, the lower protection layer 20 may protect the display panel 10
from the outside. As an example, the lower protection layer 20 may absorb physical
impacts from the outside and block the penetration of foreign substance or moisture,
etc. into the display panel 10.
[0085] In an embodiment, the front display area FDA may be flat. The second side display
area SDA2 and the third side display area SDA3 may be bent while having an arbitrary
curvature radius. As an example, a second curvature radius r2 of the second side display
area SDA2 may be different from a first curvature radius r1 of the third side display
area SDA3. As another example, the second curvature radius r2 of the second side display
area SDA2 may be the same as the first curvature radius r1 of the third side display
area SDA3. Hereinafter, the case where the second curvature radius r2 of the second
side display area SDA2 is different from the first curvature radius r1 of the third
side display area SDA3 is mainly described in detail.
[0086] Though not shown in FIG. 4A, the first side display area SDA1 (see FIG. 2) may be
the same as or similar to the third side display area SDA3, and the fourth side display
area SDA4 (see FIG. 2) may be the same as or similar to the second side display area
SDA2. Hereinafter, for convenience of description, the case where the first side display
area SDA1 and the third side display area SDA3 have the first curvature radius r1,
and the second side display area SDA2 and the fourth side display area SDA4 have the
second curvature radius r2 is mainly described in detail.
[0087] Referring to FIG. 4B, the corner display area CDA may be arranged on the corner side
of the front display area FDA, and the intermediate display area MDA may be arranged
between the corner display area CDA and the front display area FDA. The intermediate
display area MDA and the corner display area CDA may be bent with a third curvature
radius r3 that varies depending on a position. As an example, in the case where the
first curvature radius r1 of the first side display area SDA1 is different from the
second curvature radius r2 of the second side display area SDA2, the corner display
area CDA adjacent to the first side display area SDA1 and the second side display
area SDA2 may have the third curvature radius r3 that gradually varies within the
range between the first curvature radius r1 and the second curvature radius r2.
[0088] FIG. 5 is a plan view of a portion of a display panel of the display apparatus 1
according to an embodiment. FIG. 5 shows the display panel 10 before the bending.
[0089] Referring to FIG. 2, the display panel 10 may include the display area DA and the
non-display area NDA. The display area DA of the display panel 10 may include the
front display area FDA, the side display area SDA, the intermediate display area MDA,
and the corner display area CDA. The non-display area NDA of the display panel 10
may include a peripheral area PA, a bending area BA, and a pad area PDA, the peripheral
area PA being outside the display area DA, the bending area BA being on one side of
the peripheral area PA, and the pad area PDA being apart from the peripheral area
PA with the bending area BA therebetween. The display area DA and the non-display
area NDA of the display panel 10 may correspond to the display area DA and the non-display
area NDA of the display apparatus 1 (see FIG. 2), respectively, described with reference
to FIG. 2. Hereinafter, for convenience of description, the case where the peripheral
area PA surrounds the display area DA entirely as shown in FIG. 5 is described.
[0090] The display panel 10 may be bent in the bending area BA such that the display area
DA overlaps the pad area PDA in the thickness direction (that is, a z-direction) of
the display panel 10. That is, the display panel 10 may be bent such that the pad
area PDA may be arranged on the rear surface of the display panel 10 to overlap the
display area DA in a plan view. Through this structure, the area of the non-display
area NDA may be reduced and the ratio of the display area DA may be increased in the
display apparatus 1 that is completed.
[0091] A display driver 32 and a display circuit board 31 may be arranged in the pad area
PDA. The display driver 32 may receive controls signals and power voltages and generate
and output signals and voltages for driving the display panel 10. The display driver
32 may include an integrated circuit ("IC").
[0092] The display circuit board 31 may be electrically connected to the display panel 10.
As an example, though not shown in FIG. 2, the display circuit board 31 may be electrically
connected to a pad portion (not shown) arranged in the pad area PDA through an anisotropic
conductive film.
[0093] The display circuit board 31 may be a flexible printed circuit board ("FPCB") that
is bendable or a rigid printed circuit board ("PCB") that is hard and not easily bendable.
Depending on the case, the display circuit board 31 may be a composite printed circuit
board including both a rigid PCB and an FPCB.
[0094] A sensor driver 33 may be arranged on the display circuit board 31. The sensor driver
33 may include an integrated circuit. The sensor driver 33 may be attached to or built
in the display circuit board 31. The sensor driver 33 may be electrically connected
to sensing electrodes of a touch sensing layer of the display panel 10 through the
display circuit board 31.
[0095] In addition, a power supply portion (not shown), etc. may be additionally arranged
on the display circuit board 31, the power supply portion supplying voltages for driving
pixel circuits of the display panel 10, a scan driver, and the display driver 32.
In an embodiment, the power supply portion may be integrated with the display driver
32. In this case, the display driver 32 and the power supply portion may be implemented
as one integrated circuit.
[0096] In addition, the display circuit board 31 may be electrically connected to a main
circuit board (not shown). The main circuit board may include a central processing
unit ("CPU"), a graphic processing unit ("GPU"), a memory, a communication chip, digital
signal processing ("DSP"), information strategic planning ("ISP"), and a main processor
such as an application processor including various kinds of interfaces.
[0097] The display panel 10 may include a substrate 100. Various kinds of elements constituting
the display panel 10 may be arranged on the substrate 100. As an example, a plurality
of light-emitting elements constituting the display area DA, pixel circuits, signal
lines and/or voltage lines, and driving circuits, etc., may be arranged on the substrate
100, the pixel circuits driving the light-emitting elements, and the signal lines
and/or the voltage lines providing signals and/or voltages to the pixel circuits.
The display driver 32 and the display circuit board 31 may be also arranged on the
substrate 100. In an embodiment, the display driver 32 and the display circuit board
31 may be arranged over the substrate 100. In another embodiment, in the case where
a hole is bored in the substrate 100 and a wiring is arranged in the hole, the display
driver 32 and the display circuit board 31 may be arranged under the substrate 100.
[0098] FIGS. 6A and 6B are enlarged plan views of a portion of a display panel according
to an embodiment. A region A of FIGS. 6A and 6B may correspond to a region A of FIG.
5. FIG. 6A shows a figure before the display panel 10 is bent, and FIG. 6B shows a
figure after the display panel 10 is bent and transformed.
[0099] Referring to FIG. 6A, the display panel 10 may define the substrate 100 including
a plurality of through-portions PNP and include a plurality of base portions BSP that
are apart from each other by the plurality of through-portions PNP. In an embodiment,
the plurality of through-portions PNP and the plurality of base portions BSP may be
arranged in the corner display area CDA of the substrate 100 and may extend in an
outer direction away from the front display area FDA of the substrate 100.
[0100] In an embodiment, as an example, the plurality of base portions BSP may each have
a shape extending long (e.g. elongated) in the outer direction away from the front
display area FDA of the substrate 100. That is, the extension length of the plurality
of base portions BSP may be greater than the width of the base portions BSP in a direction
crossing the extension direction. One end of the plurality of base portions BSP may
be connected to a portion of the substrate 100, and the opposite end of the plurality
of base portions BSP may constitute the corner of the substrate 100.
[0101] The plurality of base portions BSP may be arranged in parallel to each other or arranged
radially. In an embodiment, in the case where the plurality of base portions BSP are
arranged in parallel to each other, an interval e between two base portions BSP that
are adjacent to each other may be constant in the extension direction of the base
portion BSP. In another embodiment, in the case where the plurality of base portions
BSP are arranged radially, the interval e between two base portions BSP that are adjacent
to each other may gradually increase in the extension direction of the base portion
BSP. Hereinafter, for convenience of description, the case where the plurality of
base portions BSP are arranged radially as shown in FIG. 6A is described.
[0102] Elements such as the pixel circuits, the light-emitting elements, the signal lines,
etc., may be arranged on the plurality of base portions BSP. The plurality of pixels
PX may be arranged in each of the plurality of base portions BSP. In an embodiment,
the plurality of pixels PX may include a red sub-pixel Pr, a green sub-pixel Pg, and
a blue sub-pixel Pb. The corner display area CDA may be implemented through the pixels
PX on the plurality of base portions BSP.
[0103] The through-portion PNP may be arranged between two base portions BSP that are adjacent
to each other among the plurality of base portions BSP. The through-portion PNP may
be defined by two base portions BSP that are adjacent to each other and a portion
connected to the two base portions BSP. The through-portion PNP may extend in an extension
direction of the base portion BSP. The through-portion PNP may pass through the upper
surface and the lower surface of the display panel 10 and reduce the weight of the
display panel 10. Two base portions BSP that are adjacent to each other among the
plurality of base portions BSP may be apart by a preset interval e from each other
by the through-portion PNP. The through-portion PNP may provide a separation region
W between the two base portions BSP that are adjacent to each other. That is, each
through-portion PNP may overlap the separation region W in a plan view.
[0104] Referring to FIG. 6B, when external force (e.g., bending force or compressing force,
etc.) is applied to the display panel 10, the positions of the plurality of base portions
BSP may change and the shape of the separation region W between the two base portions
BSP that are adjacent to each other may change. Through this structure, both contracting
and stretching characteristics may be given to the display panel 10. As an example,
when external force is applied to the base portions BSP, each of the base portions
BSP may extend in the extension direction, and simultaneously, the area of the separation
region W between the two base portions BSP that are adjacent to each other is reduced,
and thus, a compression effect may be provided. In addition, in an embodiment, the
base portions BSP may each be bent at different curvatures.
[0105] Through this structure of the substrate 100, even when the corner display area CDA
of the substrate 100 is bent, the damage to the elements arranged in the corner display
area CDA of the substrate 100 may be effectively prevented. Because the elements may
be arranged in the corner display area CDA of the substrate 100 without damage, the
pixels PX may be stably formed in the corner display area CDA. Accordingly, the corner
display area CDA of the display apparatus 1 may be implemented, and through this,
the display area DA of the display apparatus 1 may be extended.
[0106] FIG. 7 is a cross-sectional view of a portion of the display panel 10 of the display
apparatus 1 according to an embodiment.
[0107] Referring to FIG. 7, the display panel 10 may include the substrate 100, a pixel
circuit layer PCL, a display layer DISL, a thin-film encapsulation layer TFE, and
a touch sensing layer TSL.
[0108] The substrate 100 may have a multi-layered structure including a base layer and an
inorganic layer, the base layer including a polymer resin. As an example, the substrate
100 may include a base layer and a barrier layer, the base layer including a polymer
resin, and the barrier layer including an inorganic insulting layer. As an example,
the substrate 100 may include a first base layer 101, a first barrier layer 102, a
second base layer 103, and a second barrier layer 104 that are sequentially stacked.
The first base layer 101 and the second base layer 103 may include polyimide ("PI"),
polyethersulfone ("PES"), polyarylate, polyetherimide ("PEI"), polyethylene naphthalate
("PEN"), polyethylene terephthalate ("PET"), polyphenylene sulfide ("PPS"), polycarbonate
("PC"), cellulose tri acetate ("TAC") and/or cellulose acetate propionate ("CAP").
The first barrier layer 102 and the second barrier layer 104 may include an inorganic
insulating material such as silicon oxide, silicon oxynitride, and silicon nitride.
The substrate 100 may be flexible.
[0109] The pixel circuit layer PCL may be arranged on the substrate 100. The pixel circuit
layer PCL may include a pixel circuit PC including a thin-film transistor TFT and
a storage capacitor Cst. In addition, the pixel circuit layer PCL may include a buffer
layer 111, a first gate insulating layer 112, a second gate insulating layer 113,
an interlayer insulating layer 114, a first planarization insulating layer 115, and
a second planarization insulating layer 116 arranged below and/or above the elements
of the pixel circuit PC.
[0110] The buffer layer 111 may reduce or block the penetration of foreign substance, moisture,
or external air from below the substrate 100 and provide a flat surface on the substrate
100. The buffer layer 111 may include an inorganic insulating material such as silicon
oxide, silicon oxynitride, and silicon nitride and have a single-layered structure
or a multi-layered structure including the above materials.
[0111] The thin-film transistor TFT on the buffer layer 111 may include a semiconductor
layer Act. The semiconductor layer Act may include polycrystalline silicon. Alternatively,
the semiconductor layer Act may include amorphous silicon, an oxide semiconductor,
or an organic semiconductor. The semiconductor layer Act may include a channel region
C, a drain region D, and a source region S, and the drain region D and the source
region S are arranged on two opposite sides of the channel region C, respectively.
A gate electrode GE may overlap the channel region C in a plan view.
[0112] The gate electrode GE may include a low-resistance metal material. The gate electrode
GE may include a conductive material including molybdenum (Mo), aluminum (Al), copper
(Cu), and titanium (Ti) and have a single-layered structure or a multi-layered structure
including the above materials.
[0113] The first gate insulating layer 112 between the semiconductor layer Act and the gate
electrode GE may include an inorganic insulating material including silicon oxide
(SiO
2), silicon nitride (SiN
x), silicon oxynitride (SiON), aluminum oxide (Al
2O
3), titanium oxide (TiO
2), tantalum oxide (Ta
2O
5), hafnium oxide (HfO
2), or zinc oxide (ZnO
2).
[0114] The second gate insulating layer 113 may cover the gate electrode GE. Similar to
the first gate insulating layer 112, the second gate insulating layer 113 may include
an inorganic insulating material including silicon oxide (SiO
2), silicon nitride (SiN
x), silicon oxynitride (SiON), aluminum oxide (Al
2O
3), titanium oxide (TiO
2), tantalum oxide (Ta
2O
5), hafnium oxide (HfO
2), or zinc oxide (ZnO
2).
[0115] An upper electrode Cst2 of the storage capacitor Cst may be arranged on the second
gate insulating layer 113. The upper electrode Cst2 may overlap the gate electrode
GE therebelow in a plan view. In this case, the gate electrode GE and the upper electrode
Cst2 overlapping each other with the second gate insulating layer 113 therebetween
may constitute the storage capacitor Cst. That is, the gate electrode GE may serve
as a lower electrode Cst1 of the storage capacitor Cst.
[0116] As described above, the storage capacitor Cst may overlap the thin-film transistor
TFT. In an embodiment, the storage capacitor Cst may not overlap the thin-film transistor
TFT in a plan view.
[0117] The upper electrode Cst2 may include aluminum (Al), platinum (Pt), palladium (Pd),
silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir),
chrome (Cr), calcium (Ca), molybdenum (Mo), titanium (Ti), tungsten (W), and/or copper
(Cu) and include a single layer or a multi-layer including the above materials.
[0118] The interlayer insulating layer 114 may cover the upper electrode Cst2. The interlayer
insulating layer 114 may include silicon oxide (SiO
2), silicon nitride (SiN
x), silicon oxynitride (SiON), aluminum oxide (Al
2O
3), titanium oxide (TiO
2), tantalum oxide (Ta
2O
5), hafnium oxide (HfO
2), or zinc oxide (ZnO
2).The interlayer insulating layer 114 may include a single layer or a multi-layer
including the above inorganic insulating material.
[0119] The drain electrode DE and the source electrode SE may be arranged on the interlayer
insulating layer 114. The drain electrode DE and the source electrode SE may be connected
to the drain region and the source region S, respectively, through contact holes of
the insulating layers therebelow. The drain electrode DE and the source electrode
SE may each include a material having excellent conductivity. The drain electrode
DE and the source electrode SE may include a conductive material including molybdenum
(Mo), aluminum (Al), copper (Cu), and titanium (Ti) and have a single-layered structure
or a multi-layered structure including the above materials. In an embodiment, the
drain electrode DE and the source electrode SE may have a multi-layered structure
of Ti/AI/Ti.
[0120] The first planarization insulating layer 115 may cover the drain electrode DE and
the source electrode SE. The first planarization insulating layer 115 may include
an organic insulating material including a general-purpose polymer such as polymethylmethacrylate
("PMMA") or polystyrene ("PS"), polymer derivatives having a phenol-based group, an
acryl-based polymer, an imide-based polymer, an aryl ether-based polymer, an amide-based
polymer, a fluorine-based polymer, a p-xylene-based polymer, a vinyl alcohol-based
polymer, or a blend thereof.
[0121] The second planarization insulating layer 116 may be arranged on the first planarization
insulating layer 115. The second planarization insulating layer 116 may include the
same material as that of the first planarization insulating layer 115 and include
an organic insulating material including a general-purpose polymer such as polymethylmethacrylate
(PMMA) or polystyrene (PS), polymer derivatives having a phenol-based group, an acryl-based
polymer, an imide-based polymer, an aryl ether-based polymer, an amide-based polymer,
a fluorine-based polymer, a p-xylene-based polymer, a vinyl alcohol-based polymer,
or a blend thereof.
[0122] The display layer DISL may be arranged on the pixel circuit layer PCL having the
above-described structure. The display layer DISL may include a light-emitting element
200 and a pixel-defining layer 120. The light-emitting element 200 may include, for
example, an organic light-emitting diode OLED. The organic light-emitting diode OLED
may include a stack structure of a pixel electrode 210, an intermediate layer 220,
and an opposite electrode 230. The organic light-emitting diode OLED may emit, for
example, red, green, or blue light or emit red, green, blue, or white light. The organic
light-emitting diode OLED may emit light through an emission area. The emission area
may be defined as a pixel PX.
[0123] The pixel electrode 210 may be arranged on the second planarization insulating layer
116. The pixel electrode 210 may contact a contact metal CM on the first planarization
insulating layer 115 through a contact hole formed in the second planarization insulating
layer 116 and the first planarization insulating layer 115 and be electrically connected
to the thin-film transistor TFT through the contact metal CM.
[0124] The pixel electrode 210 may include a conductive oxide such as indium tin oxide ("ITO"),
indium zinc oxide ("IZO"), zinc oxide (ZnO), indium oxide (In
2O
3), indium gallium oxide ("IGO"), or aluminum zinc oxide ("AZO"). In another embodiment,
the pixel electrode 210 may include a reflective layer including silver (Ag), magnesium
(Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium
(Nd), iridium (Ir), chrome (Cr), or a compound thereof. In another embodiment, the
pixel electrode 210 may further include a layer on/under the reflective layer, the
layer including ITO, IZO, ZnO, or In
2O
3.
[0125] The pixel-defining layer 120 is arranged on the pixel electrode 210, the pixel-defining
layer 120 defining an opening 120OP that exposes the central portion of the pixel
electrode 210. The pixel-defining layer 120 may include an organic insulating material
and/or an inorganic insulating material. The opening 120OP may define an emission
area of light emitted from the light-emitting element 200. As an example, the size/width
of the opening 120OP may correspond to the size/width of the emission area. Accordingly,
the size and/or width of the pixel PX may depend on the size and/or width of the opening
120OP of the pixel-defining layer 120.
[0126] The intermediate layer 220 may include an emission layer 222 corresponding to the
pixel electrode 210. The emission layer 222 may include a polymer organic material
or a low-molecular weight organic material that emits light of a preset color. Alternatively,
the emission layer 222 may include an inorganic light-emitting material or quantum
dots.
[0127] A first functional layer 221 and a second functional layer 223 may each be arranged
under and on the emission layer 222. The first functional layer 221 may include, for
example, a hole transport layer ("HTL"), or an HTL and a hole injection layer ("HIL").
The second functional layer 223 is an element arranged on the emission layer 222 and
may include an electron transparent layer ("ETL") and/or an electron injection layer
("EIL"). Like the opposite electrode 230, the first functional layer 221 and/or the
second functional layer 223 may be common layers formed to cover the substrate 100
entirely.
[0128] The opposite electrode 230 may be arranged on the pixel electrode 210 and may overlap
the pixel electrode 210 in a plan view. The opposite electrode 230 may include a conductive
material having a small work function. As an example, the opposite electrode 230 may
include a (semi) transparent layer including silver (Ag), magnesium (Mg), aluminum
(Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium
(Ir), chrome (Cr), lithium (Li), calcium (Ca), or an alloy thereof. Alternatively,
the opposite electrode 230 may include a layer on the (semi) transparent layer, the
layer including ITO, IZO, ZnO, or In
2O
3. The opposite electrode 230 may be formed as one body to cover the substrate 100
entirely.
[0129] The display panel 10 includes a plurality of light-emitting elements 200. The plurality
of light-emitting elements emit light through the pixels PX, thereby displaying an
image. That is, the display area DA (see FIG. 2) may be defined by the plurality of
light-emitting elements 200.
[0130] The thin-film encapsulation layer TFE may be arranged on the opposite electrode 230
and may cover the light-emitting elements 200 of the display layer DISL. The thin-film
encapsulation layer TFE may include at least one inorganic encapsulation layer and
at least one organic encapsulation layer. In an embodiment, it is shown in FIG. 7
that the thin-film encapsulation layer TFE includes a first inorganic encapsulation
layer 310, an organic encapsulation layer 320, and a second inorganic encapsulation
layer 330 that are sequentially stacked.
[0131] The first inorganic encapsulation layer 310 and the second inorganic encapsulation
layer 330 may include at least one inorganic material from among aluminum oxide, titanium
oxide, tantalum oxide, hafnium oxide, or zinc oxide, silicon oxide, silicon nitride,
and silicon oxynitride. The organic encapsulation layer 320 may include a polymer-based
material. The polymer-based material may include an acryl-based resin, an epoxy-based
resin, polyimide, and polyethylene. In an embodiment, the organic encapsulation layer
320 may include acrylate. The organic encapsulation layer 320 may be formed by hardening
monomer or coating polymer. The organic encapsulation layer 320 may have transparency.
[0132] The touch sensing layer TSL may be arranged on the thin-film encapsulation layer
TFE. In an embodiment, as shown in FIG. 7, the touch sensing layer TSL may be directly
formed on the thin-film encapsulation layer TFE. In this case, an adhesive layer may
not be arranged between the touch sensing layer TSL and the thin-film encapsulation
layer TFE.
[0133] The touch sensing layer TSL may obtain coordinate information corresponding to an
external input, for example, a touch event. The touch sensing layer TSL may include
a sensing electrode and signal lines connected to the sensing electrode. The touch
sensing layer TSL may sense an external input through a mutual-capacitive method or
a self-capacitive method.
[0134] In the above, though description has been made to the case where the display apparatus
1 includes the organic light-emitting diode OLED as a light-emitting element, the
display apparatus 1 according to an embodiment is not limited thereto. In another
embodiment, the display apparatus 1 may be a light-emitting display apparatus including
an inorganic light-emitting diode, that is, an inorganic light-emitting display. In
another embodiment, the display apparatus 1 may be a quantum-dot light-emitting display.
However, for convenience of description, the case where the display apparatus 1 includes
an organic light-emitting diode OLED is described below.
[0135] FIG. 8 is an equivalent circuit diagram of a pixel circuit of a display apparatus
according to an embodiment.
[0136] Referring to FIG. 8, the pixel circuit PC may include a plurality of thin-film transistors
TFT (see FIG. 7) and the storage capacitor Cst and be electrically connected to the
organic light-emitting diode OLED. In an embodiment, the pixel circuit PC may include
a driving thin-film transistor T1, a switching thin-film transistor T2, and the storage
capacitor Cst.
[0137] The switching thin-film transistor T2 may be connected to a scan line SL and a data
line DL and configured to transfer a data signal or a data voltage to the driving
thin-film transistor T1 based on a scan signal or a switching voltage input from the
scan line SL, the data signal or the data voltage being input from the data line DL.
The storage capacitor Cst may be connected to the switching thin-film transistor T2
and a driving voltage line PL and configured to store a voltage corresponding to a
difference between a voltage transferred from the switching thin-film transistor T2
and a first power voltage ELVDD supplied to the driving voltage line PL.
[0138] The driving thin-film transistor T1 may be connected to the driving voltage line
PL and the storage capacitor Cst and configured to control a driving current flowing
from the driving voltage line PL to the organic light-emitting diode OLED according
to the voltage stored in the storage capacitor Cst. The opposite electrode (e.g.,
a cathode) of the organic light-emitting diode OLED may receive a second power voltage
ELVSS. The organic light-emitting diode OLED may emit light having a preset brightness
according to the driving current.
[0139] Though it has been described that the pixel circuit PC includes two thin-film transistors
and one storage capacitor, the embodiment according to the invention is not limited
thereto. As an example, the pixel circuit PC may include three or more thin-film transistors
and/or two or more storage capacitors in another embodiment. In still another embodiment,
the pixel circuit PC may include seven thin-film transistors and one storage capacitor.
The number of thin-film transistors and the number of storage capacitors may be variously
modified depending on the design of the pixel circuit PC. However, for convenience
of description, the case where the pixel circuit PC includes two thin-film transistors
and one storage capacitor is described below.
[0140] FIGS. 9A to 9F are side views showing a method of manufacturing a display apparatus
according to an embodiment.
[0141] First, referring to FIG. 9A, the display panel 10 may be prepared. The display panel
10 includes the display area DA, the peripheral area PA, the bending area BA, and
the pad area PDA. The peripheral area PA is outside the display area DA, the bending
area BA is disposed on one side of the peripheral area PA, and the pad area PDA is
spaced apart from the peripheral area PA with the bending area BA therebetween.
[0142] According to an embodiment, a first protection film PF1 and a second protection film
PF2 may be attached to the rear surface and the front surface of the display panel
10, respectively. The first protection film PF1 and the second protection film PF2
may protect the surfaces of the display panel 10. As an example, the first protection
film PF1 and the second protection film PF2 may include a polymer resin. Here, the
front surface of the display panel 10 denotes a surface in a direction in which the
display panel 10 displays an image, and the rear surface of the display panel 10 denotes
a surface opposite the front surface.
[0143] Next, referring to FIG. 9B, the first protection film PF1 attached to the rear surface
of the display panel 10 is removed and then the lower protection layer 20 may be attached
to the rear surface of the display panel 10. The lower protection layer 20 may be
attached to the rear surface of the display panel 10 in the form of a film through
an adhesive member. For the adhesive member, a general adhesive known in the art may
be employed without limitation. As an example, the adhesive member may be an optically
clear adhesive (OCA) or a pressure sensitive adhesive (PSA).
[0144] The lower protection layer 20 may protect the display panel 10 from an external impact
in the rear surface of the display panel 10. In addition, the lower protection layer
20 may help the display panel 10 to be easily bent in a desired region.
[0145] In an embodiment, the lower protection layer 20 may include a first portion 21 and
a second portion 22. The first portion 21 corresponds to the display area DA and the
peripheral area PA of the display panel 10, and the second portion 22 corresponds
to the pad area PDA of the display panel 10. Here, 'correspond' may mean that elements
overlap each other in a view in a direction (e.g., a z-direction) perpendicular to
one surface (e.g., the front surface or the rear surface) of the display panel 10
(i.e., in a plan view). The first portion 21 of the lower protection layer 20 may
be apart (e.g. separated) from the second portion 22. As an example, the first portion
21 may be apart from the second portion 22 with the bending area BA therebetween in
a plan view. The lower protection layer 20 may be formed by attaching the lower protection
layer 20 to the rear surface of the entire display panel 10 and patterning the lower
protection layer 20 with a laser. As described above, because the first portion 21
of the lower protection layer 20 is apart from the second portion 22 with the bending
area BA therebetween, the display panel 10 may be easily bent in the bending area
BA as described below.
[0146] Referring to FIG. 9C, the second protection film PF2 attached on the front surface
of the display panel 10 is removed and then the functional layer FL, a bending protection
layer BPL, and the display circuit board 31 may be attached to the front surface of
the display panel 10. As an example, the lower protection layer 20 is attached to
the rear surface of the display panel 10 and then the functional layer FL, the bending
protection layer BPL, and the display circuit board 31 may be attached to the display
area DA, the bending area BA, and the pad area PDA of the front surface of the display
panel 10, respectively.
[0147] The functional layer FL, the bending protection layer BPL, and the display circuit
board 31 may each be attached to the front surface of the display panel 10 through
an adhesive member. The adhesive member may be, for example, an optically clear adhesive
(OCA) or a pressure sensitive adhesive (PSA). The functional layer FL has been described
above with reference to FIG. 4A and the display circuit board 31 has been described
above with reference to FIG. 5, and thus, repeated descriptions thereof are omitted.
[0148] The bending protection layer BPL may correspond to the bending area BA of the display
panel 10. The bending protection layer BPL may include, for example, a polymer resin
such as polyethylene terephthalate (PET) and polyimide (PI).
[0149] The bending protection layer BPL may protect the display panel 10 from an external
impact in the bending area BA and support the display panel 10 such that the shape
of the display panel 10 is in a good state while the display panel 10 is bent.
[0150] Next, referring to FIG. 9D, a guide film GF may be attached to the rear surface of
the lower protection layer 20. Here, the 'rear surface' of the lower protection layer
20 means a surface opposite the surface of the lower protection layer 20 attached
to the display panel 10. In FIG. 9D, the rear surface of the lower protection layer
20 may be a surface facing a (-) z-direction (i.e., bottom surface). The guide film
GF may be attached to the rear surface of the lower protection layer 20 through an
adhesive member. The adhesive member may be, for example, an optically clear adhesive
(OCA) or a pressure sensitive adhesive (PSA).
[0151] Referring to FIG. 9E, the cover window CW may be prepared. The cover window CW may
be attached to the display panel 10. That is, the display panel 10 may be attached
to the cover window CW such that the front surface of the display panel 10 faces the
cover window CW.
[0152] In an embodiment, when the cover window CW is attached to the display panel 10, the
guide film GF may be used to improve adhesive quality therebetween. As an example,
after the display panel 10 is preliminarily formed by using the guide film GF, the
display panel 10 may be attached to the cover window CW. The preliminary forming of
the display panel 10 may be achieved by applying tensile force to the guide film GF
and transforming the shape of the display panel 10.
[0153] The operation of preparing the cover window CW and the operation of preliminarily
forming the display panel 10 are described in detail below with reference to FIGS.
11A to 11J.
[0154] Referring to FIG. 9F, the display panel 10 is attached to the cover window CW and
then the guide film GF may be removed. Then, a portion of the display panel 10 may
be bent. As an example, the bending area BA of the display panel 10 may be bent such
that the display circuit board 31 attached to the display panel 10 overlaps the display
panel 10 on the rear surface of the lower protection layer 20 in a plan view. In this
case, because the first portion 21 of the lower protection layer 20 is apart from
the second portion 22 with the bending area BA therebetween, the display panel 10
may be more easily bent in the bending area BA.
[0155] As described above, because the display panel 10 is bent such that the pad area PDA
of the display panel 10, which is a portion of the non-display area NDA, overlaps
the display area DA of the display panel 10, an area of the non-display area NDA that
is viewed from outside may be reduced when the front surface of the display panel
10 is viewed (i.e., in a plan view).
[0156] In an embodiment, before a portion of the display panel 10 is bent, a panel protection
member PPM may be arranged on the rear surface of the display panel 10. As an example,
the panel protection member PPM may be attached to the rear surface of the lower protection
layer 20 through an adhesive member. The adhesive member may be, for example, an optically
clear adhesive (OCA) or a pressure sensitive adhesive (PSA).
[0157] The panel protection member PPM may protect the display panel 10 from external impacts,
etc. and discharge heat from the display panel 10 to the outside. As an example, the
panel protection member PPM may include at least one of a light-absorbing layer for
absorbing light incident from the outside, a cushion layer for absorbing external
impacts, and a heat-dissipating layer for efficiently dissipating heat from the display
panel 10.
[0158] FIG. 10 is a plan view of a guide film GF and the lower protection layer 20 according
to an embodiment. FIG. 10 shows the lower protection layer of the display apparatus
and the guide film attached to the rear surface of the lower protection layer configured
to preliminary form the display panel.
[0159] Referring to FIG. 10, the guide film GF used for manufacturing the display apparatus
1 (see FIG. 2) may include a central area MA and edge areas EA connected to edges
of the central area MA, respective, as an embodiment. As an example, the guide film
GF may include a first edge area EA1, a second edge area EA2, a third edge area EA3,
and a fourth edge area EA4. The first edge area EA1 is connected to a first edge MA-E1
of the central area MA, the second edge area EA2 is connected to a second edge MA-E2
of the central area MA, the third edge area EA3 is connected to a third edge MA-E3
of the central area MA, and the fourth edge area EA4 is connected to a fourth edge
MA-E4 of the central area MA.
[0160] Though it is shown in FIG. 10 that the guide film GF includes four edge areas EA,
the embodiment according to the invention is not limited thereto, and the guide film
GF may include a smaller number of edge areas EA or a greater number of edge areas
EA depending on the shape of the display apparatus 1. In addition, though it is shown
in FIG. 10 that the edge area EA has a quadrangular shape in a plan view, the edge
area EA may have a polygon such as a triangle, a portion of a circle, a portion of
an ellipse in another embodiment. However, the edge area EA may have various shapes.
[0161] In an embodiment, the guide film GF may be attached to the rear surface of the lower
protection layer 20 to overlap the lower protection layer 20 in a plan view. The central
area MA of the guide film GF may be attached to overlap the first portion 21 of the
lower protection layer 20. At least one edge area EA of the guide film GF may be attached
to overlap the second portion 22 of the lower protection layer 20. As an example,
the first edge area EA1 of the guide film GF may be attached to overlap the second
portion 22 of the lower protection layer 20 in a plan view. Though it is shown in
FIG. 10 that the edge of the first portion 21 of the lower protection layer 20 coincides
with the edge of the central area MA of the guide film GF, the embodiment according
to the invention is not limited thereto.
[0162] As described above, the lower protection layer 20 may include the first portion 21
and the second portion 22. The first portion 21 corresponds to the display area DA
(see FIG. 5) and the peripheral area PA (see FIG. 5) of the display panel 10 (see
FIG. 5), and the second portion 22 corresponds to the pad area PDA (see FIG. 5) of
the display panel 10. Specifically, the first portion 21 of the lower protection layer
20 may correspond to the front display area FDA, the side display area SDA, the intermediate
display area MDA, and the corner display area CDA of the display panel 10.
[0163] The first portion 21 of the lower protection layer 20 may have a shape corresponding
to the display area DA and the peripheral area PA of the display panel 10 in a plan
view. As an example, the first portion 21 may have, as a whole, a quadrangular shape
in which corners are round in a plan view as shown in FIG. 10. The second portion
22 of the lower protection layer 20 may have, as a whole, a quadrangular shape in
a plan view. However, the shape according to the invention is not limited thereto.
[0164] In an embodiment, the lower protection layer 20 may include the first portion 21
and the second portion 22 including different materials. As an example, the modulus
(e.g. the Young's modulus, or modulus of elasticity) of the first portion 21 of the
lower protection layer 20 may be less than the modulus of the second portion 22 of
the lower protection layer 20. That is, the first portion 21 of the lower protection
layer 20 may include a material having a relatively small modulus, and the second
portion 22 of the lower protection layer 20 may include a material having a relatively
large modulus.
[0165] In an embodiment, as an example, the first portion 21 of the lower protection layer
20 may include poly dimethylsiloxane ("PDMS"). As another example, the first portion
21 of the lower protection layer 20 may include thermoplastic polyurethane ("TPU").
As an example, the modulus of the first portion 21 of the lower protection layer 20
may be greater than 0 megapascals (MPa) and equal to or less than 100 MPa. As an example,
the second portion 22 of the lower protection layer 20 may include polyethylene terephthalate
(PET). As an example, the modulus of the second portion 22 of the lower protection
layer 20 may be about 600 MPa to about 2000 MPa.
[0166] The first portion 21 of the lower protection layer 20 may help the corner display
area CDA (see FIG. 5) of the display panel 10 to be properly bent while the display
panel 10 is preliminarily formed through the guide film GF.
[0167] As a comparative example, in the case where the lower protection layer 20 is not
provided, even when the side display area SDA (see FIG. 5) of the display panel 10
is properly bent while the display panel 10 is preliminarily formed through the guide
film GF, the corner display area CDA of the display panel 10 may be incompletely bent.
As another comparative example, even though the lower protection layer 20 corresponding
to the display area DA is provided, when the modulus of the lower protection layer
20 is relatively large, the lower protection layer 20 may not be swiftly transformed
and large compression stress is formed, and the corner display area CDA of the display
panel 10 may be incompletely bent.
[0168] With this state, when the display panel 10 is attached to the cover window CW, the
corner display area CDA of the display panel 10 that is incompletely bent may be pressed
by the corner portion of the cover window CW, and thus, may receive excessive pressure.
Accordingly, the corner display area CDA of the display panel 10 may be damaged or
buckling or wrinkles may occur. Alternatively, an unexpected space may be formed between
the display panel 10 and the cover window CW due to the incomplete bending in the
corner display area CDA of the display panel 10. Air bubbles may be trapped in this
space.
[0169] In contrast, according to an embodiment, the first portion 21 of the lower protection
layer 20 may help the corner display area CDA of the display panel 10 to be properly
bent, the first portion 21 having a relatively small modulus (exceeding 0 MPa and
equal to or less than 100 MPa) and corresponding to the display area DA of the display
panel 10. Accordingly, the incomplete bending of the corner display area CDA of the
display panel 10 may be effectively prevented or reduced.
[0170] The second portion 22 of the lower protection layer 20 may help the display circuit
board 31 (see FIG. 5) and/or the display driver 32 (see FIG. 5) to be properly mounted
or attached in the pad area PDA. While the display circuit board 31 and/or the display
driver 32 are mounted or attached, a preset pressure is applied to the display panel
10. In this case, when the lower protection layer 20 arranged in the pad area PDA
has a relatively small modulus, a defect probability may be increased due to repulsive
force against the pressure. In contrast, according to an embodiment, the second portion
22 of the lower protection layer 20 that corresponds to the pad area PDA of the display
panel 10 may have a relatively large modulus, which reduces repulsive force in the
pad area PDA and helps the display circuit board 31 and/or the display driver 32 to
be properly mounted or attached while the display circuit board 31 and/or the display
driver 32 are mounted or attached.
[0171] In an embodiment, the guide film GF may have a modulus greater than the modulus of
the first portion 21 of the lower protection layer 20. As an example, the guide film
GF may include polyethylene terephthalate (PET), and the modulus of the guide film
GF may be about 600 MPa to about 2000 MPa.
[0172] As a comparative example, in the case where the guide film GF includes poly dimethylsiloxane
(PDMS) like the first portion 21 of the lower protection layer 20, the thickness of
the guide film GF increases due to the relatively small modulus of the guide film
GF. Due to this, the display panel 10 may become uneven while the display panel 10
is preliminarily formed. In addition, because poly dimethylsiloxane (PDMS) includes
silicon (Si), the guide film GF may stick to the stage of equipment transferring the
guide film GF.
[0173] In contrast, to resolve this issue, in an embodiment, the guide film GF may include
a material having a relatively large modulus, for example, include polyethylene terephthalate
(PET).
[0174] In an embodiment, with the guide film GF attached on the rear surface of the lower
protection layer 20, the intermediate area MA of the guide film GF may include a concave
corner CC not to overlap the corner display area CDA of the display panel 10 in a
plan view. That is, as shown in FIG. 5, before the display panel 10 is bent, the corner
display area CDA of the display panel 10 may overlap the lower protection layer 20
and may not overlap the guide film GF in a plan view. Through this, even when the
guide film GF includes a material having a relatively large modulus, it may be avoided
for the guide film GF to adversely influence the bending of the corner display area
CDA of the display panel 10.
[0175] FIGS. 11A to 11J are side views or perspective views showing a method of manufacturing
a display apparatus according to an embodiment and mainly show an operation of preparing
the cover window CW and an operation of preliminarily forming the display panel 10.
[0176] Referring to FIG. 11A, the display panel 10, the functional layer FL on the display
panel 10, and the lower protection layer 20 attached on the rear surface of the display
panel 10 are prepared. The guide film FL may be attached to the rear surface of the
lower protection layer 20.
[0177] In an embodiment, when the guide film GF is attached to the rear surface of the lower
protection layer 20, the guide film GF may be attached such that the display panel
10 corresponds to the central area MA of the guide film GF. Specifically, the guide
film GF may be attached such that all of the front display area FDA, the side display
area SDA, the intermediate display area MDA, and the corner display area CDA correspond
to the central area MA of the guide film GF. In this case, the edge areas EA (see
FIG. 10) of the guide film GF may not overlap the display panel 10 in a plan view.
[0178] Referring to FIG. 11B, to prepare the cover window CW, the cover window CW may be
transformed to have planes and curves by using a zig ZIG including a concave surface
corresponding to the final shape of the cover window CW. That is, the zig ZIG may
be a frame having the shape of the display apparatus to be finally manufactured. The
cover window CW may be transformed according to the shape of the concave surface of
the zig ZIG by closely attaching the cover window CW to the concave surface of the
zig ZIG.
[0179] Referring to FIG. 11C, a lamination apparatus LA may be prepared, the lamination
apparatus LA including a support LA1 and a volume change portion LA2 on the support
LA1. The support LA1 may support the volume change portion LA2. The volume change
portion LA2 may include an air pump or be connected to the air pump. Because the volume
change portion LA2 has a small modulus, the shape and the volume of the volume change
portion LA2 is variable according to an air pressure through the air pump. Alternatively,
the volume change portion LA2 may include a diaphragm.
[0180] The rear surface of the display panel 10 may be arranged to face the lamination apparatus
LA. That is, the guide film GF may be arranged on the side of the lamination apparatus
LA. Next, the display panel 10 may be aligned with the lamination apparatus LA. As
an example, the display panel 10 may be aligned with the lamination apparatus LA such
that a first alignment key AK1 marked on the display panel 10 coincides with a second
alignment key AK2 marked on the lamination apparatus LA.
[0181] Referring to FIG. 11D, the display panel 10 may be preliminarily formed through the
guide film GF. As an example, the shape of the display panel 10 may be transformed
by applying external force, for example, tensile force to the guide film GF.
[0182] Specifically, the guide film GF may be seated on the lamination apparatus LA. A push
member PM may be arranged on the guide film GF. The guide film GF may be closely attached
to the lateral side of the lamination apparatus LA by using the push member PM. As
an example, because push members PM press the edge areas EA of the guide film GF,
respectively, tensile force may be applied to the guide film GF. As the guide film
GF is transformed along the outer surface of the lamination apparatus LA, the display
panel 10 on the guide film GF may be appropriately bent and transformed.
[0183] Referring to FIG. 11E, the shape of the display panel 10 that is preliminarily formed
through the guide film GF may be shown.
[0184] Referring to FIG. 11F, after the display panel 10 is preliminarily formed, the front
surface of the display panel 10 is arranged to face the cover window CW, and the display
panel 10 may be aligned with the cover window CW. The display panel 10 may be aligned
with the cover window CW such that the first alignment key AK1 marked on the display
panel 10 coincides with a third alignment key AK3 marked on the cover window CW.
[0185] Referring to FIGS. 11G and 11H, the cover window CW may be attached on the front
surface of the display panel 10. As an example, as shown in FIG. 11G, first, a portion
of the display panel 10 (e.g. at a first place) may be attached on the cover window
CW. A flat surface (e.g., the front display area FDA) having no curvature in the final
shape of the display panel 10 may be attached on the cover window CW on the first
place.
[0186] Next, as shown in FIG. 11H, as the shape of the volume change portion LA2 of the
lamination apparatus LA changes and the volume thereof increases, the remaining portions
of the display panel 10, for example, the side display area SDA and the corner display
area CDA may be attached to the cover window CW.
[0187] An operation of attaching the side display area SDA to the cover window CW and an
operation of attaching the corner display area CDA to the cover window CW may be simultaneously
performed. As an example, while the side display area SDA is attached to the cover
window CW, the corner display area CDA may naturally contact and stick to the cover
window CW due to peripheral external force. As another example, an operation of attaching
the side display area SDA to the cover window CW and an operation of attaching the
corner display area CDA to the cover window CW may be performed at different times.
As an example, the side display area SDA may be attached to the cover window CW first,
and then the corner display area CDA may be attached to the cover window CW.
[0188] Referring to FIG. 11i, after an operation of attaching the display panel 10 to the
cover window CW is performed, the guide film GF may be removed from the display panel
10 to which the cover window CW has been attached. As an example, the guide film GF
may be separated from the display panel 10 by irradiating ultraviolet ("UV") to an
adhesive member (not shown) that attaches the guide film GF to the display panel 10
and weakening adhesive force of the adhesive member.
[0189] Referring to FIG. 11J, an operation of hardening the cover window CW and the display
panel 10 may be performed. As an example, the hardening may be performed by irradiating
UV to the cover window CW and the display panel 10. When UV is irradiated to the cover
window CW and the display panel 10, air bubbles, etc. may escape from the adhesive
member, etc. attached to the display panel 10.
[0190] Though the contents disclosed with reference to FIGS. 3 to 11J up to this point have
been disclosed as an example of the display apparatus 1 of FIG. 2, the above descriptions
are equally applicable to the display apparatus 1 of FIG. 1. In this case, the disclosure
regarding the corner display area CDA of the display apparatus 1 of FIG. 2 is applicable
to the corner area CA of the display apparatus 1 of FIG. 1.
[0191] According to an embodiment, the display apparatus which may display an image even
on a lateral surface and/or a corner to reduce the area of the non-display area and
increase the area of the display area, and a manufacturing method thereof may be implemented.
In addition, when the display panel is attached to the cover window while the display
apparatus is manufactured, damage to the corner portion of the display panel may be
effectively prevented or reduced, or bucking, wrinkles, etc. may be effectively prevented
from occurring. Through this, quality and yields may be effectively improved. However,
the scope of the present disclosure is not limited by this effect.
[0192] It should be understood that embodiments described herein should be considered in
a descriptive sense only and not for purposes of limitation. Descriptions of features
or aspects within each embodiment should typically be considered as available for
other similar features or aspects in other embodiments. While one or more embodiments
have been described with reference to the figures, it will be understood by those
of ordinary skill in the art that various changes in form and details may be made
therein without departing from the scope as defined by the following claims.